Domestication method of microalgae and application of domesticated microalgae in treatment of sulfur-containing gas

Abstract

The invention relates to the field of microalgae culture, in particular to a microalgae domestication method and application of domesticated microalgae produced by the method in treatment of sulfur-containing gas. The domestication method of the microalgae comprises the following steps: inoculating the microalgae to a domestication culture medium, introducing sulfur-containing gas, and sequentially carrying out at least two stages of domestication culture to obtain the domesticated microalgae. By adopting the domestication method of the microalgae, provided by the invention, the sulfur resistance and the desulfurization efficiency can be remarkably improved.

Description

Technical Field

[0001] The invention relates to the field of microalgae cultivation, and in particular to a microalgae domestication method and application of the domesticated microalgae produced by the method in treating sulfur-containing gas. Background Art

[0002] Microalgae are a type of single-cell or simple multicellular photosynthetic microorganisms. Currently, the microalgae that can be cultivated or produced on a large scale using biotechnology mainly include Cyanobacteria, Chlorophyta, Chrysophyta and Rhodophyta. Microalgae are widely distributed in freshwater and marine systems. Due to their high photosynthesis efficiency, fast growth rate, high oil content, no occupation of arable land, the ability to use wastewater and waste gas for cultivation, and the ability to produce throughout the year, they are increasingly playing an important role in bioenergy, biomedicine, and environmental governance.

[0003] Currently, microalgae are widely studied and used in sewage treatment, carbon dioxide capture, SO x and NO x In the fields of gas treatment, there are few studies on the technology of using microalgae to remove sulfur-containing gases, especially hydrogen sulfide gas.

[0004] At present, the commonly used methods for removing sulfur-containing gases include hydrodesulfurization, extractive desulfurization, oxidative desulfurization, and biological desulfurization. The first three have high operating costs and complex processes; biological desulfurization is to capture and adsorb specific sulfur compounds through bacteria, which has the disadvantage of limited overall rate; compared with these traditional desulfurization methods, microalgae desulfurization has the advantages of simple operation, easier cultivation, low cost, low energy consumption, long service life, wide range of use, and synthesizing biomass while removing sulfur-containing gases, and has broad application prospects. However, although a single microalgae can treat sulfur-containing gases, there are still problems such as low removal efficiency per unit time and poor sulfur tolerance of microalgae. Summary of the invention

[0005] The purpose of the present invention is to overcome the problems of low desulfurization efficiency and poor sulfur tolerance of microalgae cultivated in the prior art, and to provide a method for domesticating microalgae. The microalgae obtained by the method has high desulfurization efficiency and strong sulfur tolerance. The present invention also provides the use of the domesticated microalgae in treating sulfur-containing gases.

[0006] In order to achieve the above-mentioned object, the first aspect of the present invention provides a method for taming microalgae, wherein the method comprises: inoculating microalgae onto a taming medium, introducing sulfur-containing gas, and sequentially performing at least two stages of taming culture to obtain tamed microalgae;

[0007] Among them, in at least two stages of domestication and cultivation, the steps of domestication in each stage include:

[0008] S1: After introducing sulfur-containing gas into the acclimation medium and maintaining it for 2-15 min, ventilation is stopped and the acclimation culture is carried out for 1-6 h;

[0009] S2: Repeat step S1 at least once;

[0010] S3: Then, oxygen-containing gas is introduced into the acclimation medium and maintained for 10-30 min, and then aeration is stopped and cultured for 20-72 h;

[0011] Wherein, the concentration of the sulfur-containing gas introduced in each stage of acclimatization is greater than the concentration of the sulfur-containing gas introduced in the previous stage.

[0012] In the present invention, preferably, the microalgae are mixed microalgae, more preferably, the microalgae strains in the mixed microalgae belong to at least one of green algae, blue algae, diatoms and red algae, and further preferably, the mixed microalgae are a combination of at least two green algae, a combination of green algae and blue algae, or a combination of blue algae and diatoms.

[0013] In a preferred embodiment of the present invention, the culture pressure in step S3 is 0.1-3 MPa, more preferably 0.15-2 MPa.

[0014] The second aspect of the present invention provides the use of the domesticated microalgae obtained by the method described above in treating sulfur-containing gas.

[0015] Through the above technical solution, the method of the present invention can achieve the following beneficial effects:

[0016] (1) By inoculating a variety of microalgae, the microalgae's ability to metabolize and transform sulfide is improved, the utilization efficiency, desulfurization efficiency and sulfur tolerance of the microalgae are increased, and the problem of low desulfurization efficiency and poor sulfur tolerance of a single microalgae system is solved.

[0017] (2) Through reasonable high-density culture and enhanced domestication, a mixed microalgae system with a long life cycle and stable growth can be obtained, which can improve the microalgae's absorption of nutrients and enhance the microalgae's resistance to the environment, achieve mutual promotion and continuous and efficient coordinated growth between different microalgae, and increase the biomass of microalgae; in particular, the inventors found that when the microalgae is domesticated under positive pressure conditions, its biomass can be further increased.

[0018] (3) The microalgae cultivated by this method can absorb sulfide in sulfur-containing gas and convert it into harmless substances, which helps to reduce sulfur emissions and alleviate environmental pollution without causing secondary pollution. In addition, the growth conditions of microalgae are simple, easy to cultivate, low-cost, and suitable for a variety of scenarios. DETAILED DESCRIPTION

[0019] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0020] A first aspect of the present invention provides a method for taming microalgae, wherein the method comprises: inoculating microalgae onto a taming medium, introducing sulfur-containing gas, and sequentially performing at least two stages of taming culture to obtain tamed microalgae;

[0021] Among them, in at least two stages of domestication and cultivation, the steps of domestication in each stage include:

[0022] S1: After introducing sulfur-containing gas into the acclimation medium and maintaining it for 2-15 min, ventilation is stopped and the acclimation culture is carried out for 1-6 h;

[0023] S2: Repeat step S1 at least once;

[0024] S3: Then, oxygen-containing gas is introduced into the acclimation medium and maintained for 10-30 min, and then aeration is stopped and cultured for 20-72 h;

[0025] Wherein, the concentration of the sulfur-containing gas introduced in each stage of acclimatization is greater than the concentration of the sulfur-containing gas introduced in the previous stage.

[0026] In the present invention, the microalgae may be one type of microalgae or a mixed type of microalgae, preferably a mixed type of microalgae, for example, at least two types of microalgae from the same phylum or at least two types of microalgae from different phyla; more preferably, the microalgae strains in the mixed microalgae belong to at least one of green algae, blue algae, diatoms and red algae; further preferably, the mixed microalgae is a combination of at least two types of green algae, a combination of green algae and blue algae, or a combination of blue algae and diatoms. When the microalgae are the above combinations, the desulfurization efficiency and sulfur resistance of the domesticated mixed microalgae can be further improved.

[0027] In the present invention, preferably, the green algae is selected from at least one of Chlorella, Chlamydomonas and Scenedesmus.

[0028] In the present invention, preferably, the cyanobacteria is selected from at least one of Cyanobacterium, Oscillatoria, Nostoc and Spirulina.

[0029] In the present invention, preferably, the diatom is selected from at least one of Melostom, Chaetoceros and Cyclotella.

[0030] In the present invention, preferably, the red algae is selected from red hair algae and / or polysiphonia.

[0031] In the present invention, preferably, the weight ratio between any two algae in the mixed microalgae is 0.1-100, more preferably, the weight ratio between any two algae in the mixed microalgae is 0.5-20.

[0032] In the present invention, preferably, the volume ratio of the microalgae to the acclimation medium is 1:50-1:4.

[0033] In a preferred embodiment of the present invention, the biomass of the mixed microalgae is 2-15 g / L.

[0034] In the present invention, the sulfur-containing gas preferably includes hydrogen sulfide and / or sulfur dioxide.

[0035] In the present invention, the amount of hydrogen sulfide and / or sulfur dioxide introduced can be adjusted according to the size of the acclimation system. Preferably, the amount of hydrogen sulfide and / or sulfur dioxide introduced per liter of acclimation culture medium is 3-375 mL, preferably 25-100 mL.

[0036] In the present invention, the rate of the sulfur-containing gas can be adjusted according to the size of the acclimation system. For example, when the volume of the acclimation system is 0.1-5L, preferably, the rate of the sulfur-containing gas is 3-50mL / min, and more preferably 5-20mL / min.

[0037] In the present invention, the role of introducing sulfur-containing gas for domestication is to increase the metabolic activity and resistance of microalgae to sulfur. The concentration of the sulfur-containing gas introduced in each stage of domestication is greater than the concentration of the sulfur-containing gas introduced in the previous stage.

[0038] In a preferred embodiment of the present invention, in the at least two-stage acclimation culture, the concentration of the sulfur-containing gas introduced in the first stage is 10-120 ppm; more preferably, the concentration of the sulfur-containing gas introduced in the second stage is 80-1200 ppm. Under this preferred condition, the microalgae grows well, has improved sulfur tolerance, and has a better treatment effect on sulfur-containing gas.

[0039] In another preferred embodiment of the present invention, the at least two-stage acclimation culture includes at least three-stage acclimation culture. Further preferably, the concentration of the sulfur-containing gas introduced in the first stage is 10-120 ppm; the concentration of the sulfur-containing gas introduced in the second stage is 80-1200 ppm; the concentration of the sulfur-containing gas introduced in the third stage is 800-3000 ppm. Under this preferred condition, the growth condition of the microalgae is good, the sulfur tolerance is further improved, and the treatment effect of the sulfur-containing gas is better.

[0040] In the present invention, in step S1, the conditions for acclimation and culture include: light intensity of 100-25000 Lux, for example, it can be 100 Lux, 500 Lux, 1000 Lux, 1500 Lux, 2000 Lux, 4000 Lux, 6000 Lux, 8000 Lux, 10000 Lux, 12000 Lux, 14000 Lux, 16000 Lux, 18000 Lux, 20000 Lux, 22000 Lux, 25000 Lux and any range between any two values. Preferably, the light intensity is 2000-10000 Lux.

[0041] In the present invention, in step S1, the conditions for acclimation culture also include culture temperature and pH, etc. The culture temperature and pH conventionally used in the art can be selected according to the specific algae species. Preferably, the culture temperature is 10-45°C, more preferably 12-30°C; preferably, the culture pH is 6-9.5, more preferably 7-9.

[0042] In the present invention, the illumination source for the domestication and cultivation can be natural light or artificial light.

[0043] In the present invention, oxygen-containing gas is introduced into the algae liquid after acclimation and culture in step S2. The oxygen-containing gas can be ordinary air or other gases containing oxygen, for example, a gas having an oxygen concentration of 10 volume % or more (such as 10 volume %, 20 volume %, 40 volume %, 60 volume %, 80 volume %, etc.).

[0044] In the present invention, preferably, the amount of oxygen introduced per liter of acclimation medium is 10-1000 mL, more preferably 20-650 mL.

[0045] In the present invention, the rate of the oxygen-containing gas can be adjusted according to the size of the acclimation system. For example, when the volume of the acclimation system is 0.1-5 L, preferably, the rate of the oxygen-containing gas is 5-250 mL / min.

[0046] In the present invention, in step S3, the culture conditions include: light intensity of 100-25000 Lux, for example, it can be 100 Lux, 500 Lux, 1000 Lux, 1500 Lux, 2000 Lux, 4000 Lux, 6000 Lux, 8000 Lux, 10000 Lux, 12000 Lux, 14000 Lux, 16000 Lux, 18000 Lux, 20000 Lux, 22000 Lux, 25000 Lux and any range between any two values, preferably, the light intensity is 2000-10000 Lux; light and dark alternating culture, the light-dark ratio is 6:18-24:0, preferably 8:16-14:10.

[0047] In the present invention, in step S3, the culture pressure is normal pressure or higher than normal pressure. When the culture pressure is higher than normal pressure, the removal rate and sulfur resistance of the mixed microalgae to sulfur-containing gas will be further improved. Preferably, the pressure is 0.1-3MPa, for example, 0.1MPa, 0.15MPa, 0.2MPa, 0.5MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa and any range between any two values. More preferably, the pressure is 0.15-2MPa.

[0048] In the present invention, in step S3, the culture conditions also include: an oxidation-reduction potential (ORP) of -450 to -150 ev. When the oxidation-reduction potential is within the above range, the microalgae grows well and has a good sulfur removal effect; more preferably, the oxidation-reduction potential is -450 to -300 ev. When the oxidation-reduction potential is within the above range, the microalgae grows better and the sulfur removal effect is further improved.

[0049] In the present invention, in step S3, the culture conditions also include culture temperature, pH, dissolved oxygen content (DO), etc. The culture temperature, pH, and dissolved oxygen content conventionally used in the art can be selected according to the specific algae species. Preferably, the culture temperature is 10-45°C, more preferably 12-30°C; preferably, the culture pH is 6-9.5, more preferably 7-9; preferably, the dissolved oxygen content of the culture is below 10 mg / L, more preferably below 4 mg / L.

[0050] In the present invention, in step S3, in order to improve the light energy utilization rate of the microalgae, promote gas exchange and improve the nutrient effectiveness, stirring, shaking and other methods can be used to keep the microalgae in a suspended state. The method that can be used can achieve the purpose of suspending the microalgae and is not limited to the above.

[0051] In the present invention, in each stage of domestication, the microalgae can be collected when the biomass of the microalgae is stable. In some preferred embodiments of the present invention, the biomass of the mixed microalgae is 4-25 g / L when collected after the domestication is completed.

[0052] In the present invention, the method for collecting the domesticated microalgae is a conventional method in the art, which may be electrical treatment, sedimentation, centrifugation, flocculation, flotation, etc., as long as the purpose of harvesting the microalgae can be achieved.

[0053] In the present invention, the microalgae domestication method further comprises: before inoculating the microalgae into the domestication medium, inoculating the algae liquid containing the microalgae into the expansion culture medium for pre-culture.

[0054] The purpose of the pre-culture is to obtain more pure and strong microalgae, that is, to obtain algae species with vigorous vitality and sufficient inoculation quantity.

[0055] In the present invention, the endpoint of the pre-culture can be determined according to the density of the microalgae in the culture system. Preferably, the culture time is 3-15 days, more preferably 4-8 days.

[0056] In the present invention, the illumination intensity of the pre-culture is 100-25000 Lux, for example, it can be 100 Lux, 500 Lux, 1000 Lux, 1500 Lux, 2000 Lux, 4000 Lux, 6000 Lux, 8000 Lux, 10000 Lux, 12000 Lux, 14000 Lux, 16000 Lux, 18000 Lux, 20000 Lux, 22000 Lux, 25000 Lux and any range between any two values. Preferably, the illumination intensity is 2000-10000 Lux. The light and dark alternating culture has a light-dark ratio of 6:18-24:0, preferably 8:16-14:10.

[0057] In the present invention, the pre-culture conditions also include culture temperature and pH, etc. The culture temperature and pH conventionally used in the art can be selected according to the specific algae species. Preferably, the pre-culture temperature is 10-45°C, more preferably 12-30°C; preferably, the pre-culture pH is 6-9.5, more preferably 7-9.

[0058] In the present invention, in the pre-culture process, in order to improve the light energy utilization rate of the microalgae, promote gas exchange and improve the nutrient effectiveness, stirring, shaking and other methods can be used to keep the microalgae in a suspended state. The method that can be used can achieve the purpose of suspending the microalgae and is not limited to the above.

[0059] In the present invention, preferably, the volume ratio of the algae liquid of the pre-cultured microalgae to the expansion culture medium is 1:50-1:4.

[0060] In the present invention, the acclimation medium includes: 100-700 mg / L NaNO 3 ; 20-180mg / L KH 2 PO 4 ; 600-2500 mg / L NaHCO 3 , such as 600 mg / L, 1000 mg / L, 1400 mg / L, 1800 mg / L, 2100 mg / L, 2500 mg / L and any range between any two values; 1000-5000 mg / L of Na 2 CO 3 , for example, 1000 mg / L, 1600 mg / L, 2200 mg / L, 2800 mg / L, 3400 mg / L, 4000 mg / L, 4600 mg / L, 5000 mg / L and any range between any two values.

[0061] In the present invention, the acclimation medium further comprises: 30-180 mg / L of vitamin B1, 15-80 mg / L of vitamin B12, 1000-5000 mg / L of disodium EDTA, 3-30 mg / L of CuSO 4 , 10-60mg / L ZnSO 4 , 50-250mg / L MnCl 2 , 50-200 mg / L CaCl 2 , 20-120 mg / L CoCl 2 , 15-80 mg / L of vitamin H, such as 15 mg / L, 25 mg / L, 35 mg / L, 45 mg / L, 55 mg / L, 65 mg / L, 75 mg / L, 80 mg / L and any range between any two values.

[0062] In the present invention, the expansion culture medium includes: 200-1000 mg / L NaNO 3 20-100 mg / L NaH 2 PO 4 , 40-200mg / L KH 2 PO 4 , 70-350mg / L of Na 2 CO 3 .

[0063] In the present invention, the expansion culture medium also includes: 30-180 mg / L vitamin B1, 15-80 mg / L vitamin B12, 1000-5000 mg / L EDTA disodium, 8-60 mg / L CuSO 4, 15-85mg / L ZnSO 4 , 70-350mg / L MnCl 2 , 60-350mg / L CaCl 2 , 20-100mg / L CoCl 2 ; also includes 25-150 mg / L MgSO 4 , such as 25 mg / L, 50 mg / L, 75 mg / L, 100 mg / L, 125 mg / L, 150 mg / L and any range between any two values; also including 120-500 mg / L FeCl 3 , for example, 120 mg / L, 200 mg / L, 280 mg / L, 340 mg / L, 400 mg / L, 500 mg / L and any range between any two values.

[0064] In the present invention, the cultivation of microalgae can be carried out in an open, semi-open or fully closed cultivation system.

[0065] In the present invention, the microalgae culture method is a conventional culture method in the art, which can be static culture, suspension culture, flow culture or continuous culture.

[0066] The second aspect of the present invention provides the use of the domesticated microalgae obtained by the method as described above in treating sulfur-containing gas.

[0067] The domesticated microalgae obtained in the first aspect of the present invention can be prepared into a desulfurization liquid with a sodium carbonate solution, and the gas containing hydrogen sulfide is introduced into the desulfurization liquid. The concentration of the sodium carbonate solution can be 5-50 g / L.

[0068] Those skilled in the art can select a suitable application method according to the specific environment in which the sulfur-containing gas is generated or exists, and are not limited to the implementation method described above.

[0069] The present invention will be described in detail below through examples.

[0070] The biomass of the mixed microalgae was measured by sampling and weighing.

[0071] After treatment, H 2 The S content was measured by an online detector.

[0072] The culture medium was as follows:

[0073]

[0074]

[0075] Example 1

[0076] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0077] 1) Pre-culture

[0078] A mixed algae liquid of aseptically treated Chlorella sp. and Spirulina sp. was inoculated into a semi-open culture system containing 2 L of expansion culture medium, the weight ratio of Chlorella sp. to Spirulina was 1:1, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae liquid to the expansion culture medium was 1:10, and light-dark alternating culture was performed under the conditions of temperature 15-20°C, pH 7.5-8, light intensity 2000 Lux, and light-dark ratio 10:14, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0079] 2) The first stage of domestication

[0080] The pre-cultured mixed microalgae were transferred to a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0081] (1) A 20 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 15-20°C, a pH of 7.5-8, and a light intensity of 2000 Lux.

[0082] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 24 h under the conditions of light intensity of 2000 Lux, temperature of 15-20°C, pH of 7.5-8, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0083] 3) Second stage of domestication

[0084] (1) A 100 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the temperature was maintained for 5 min. Then, aeration was stopped and the microalgae were acclimated and cultured for 2 h at a temperature of 15-20°C, a pH of 7.5-8, and a light intensity of 2000 Lux.

[0085] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 24 h under the conditions of light intensity of 2000 Lux, temperature of 15-20°C, pH of 7.5-8, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0086] Example 2

[0087] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0088] 1) Pre-culture

[0089] A mixed algae liquid of aseptically treated Chlorella sp. and Spirulina sp. was inoculated into a semi-open culture system containing 2 L of expansion culture medium, the weight ratio of Chlorella sp. to Spirulina was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae liquid to the culture medium was 1:10, and light-dark alternating culture was performed under the conditions of temperature 15-20°C, pH 7.5-8.5, light intensity 2000 Lux, and light-dark ratio 10:14, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0090] 2) The first stage of domestication

[0091] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0092] (1) A 20 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 2000 Lux.

[0093] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 24 h under the conditions of light intensity of 2000 Lux, temperature of 15-20° C., pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0094] 3) Second stage of domestication

[0095] (1) A 100 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the temperature was maintained for 5 min. Then, aeration was stopped and the microalgae were acclimated and cultured for 2 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 2000 Lux.

[0096] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 24 h under the conditions of light intensity of 2000 Lux, temperature of 15-20° C., pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0097] 4) The third stage of domestication

[0098] (1) A 1000 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 2000 Lux.

[0099] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 24 h under the conditions of light intensity of 2000 Lux, temperature of 15-20°C, pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0100] Example 3

[0101] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0102] 1) Pre-culture

[0103] A mixed algae solution of Chlorella sp. and Chlamydomonas sp. treated aseptically was inoculated into a semi-open culture system containing 2L of expansion culture medium, the weight ratio of Chlorella sp. to Chlamydomonas sp. was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae solution to the culture medium was 1:10, and light-dark alternating culture was performed under the conditions of temperature 15-20°C, pH 7.5-8.5, light intensity 4000 Lux, and light-dark ratio 10:14, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0104] 2) The first stage of domestication

[0105] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0106] (1) A 50 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 4000 Lux.

[0107] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 24 h under the conditions of light intensity of 4000 Lux, temperature of 15-20° C., pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0108] 3) Second stage of domestication

[0109] (1) A 200 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the temperature was maintained for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 4000 Lux.

[0110] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 24 h under the conditions of light intensity of 4000 Lux, temperature of 15-20° C., pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0111] 4) The third stage of domestication

[0112] (1) A 1500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 15-20°C, a pH of 7.5-8.5, and a light intensity of 4000 Lux.

[0113] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 24 h under the conditions of light intensity of 4000 Lux, temperature of 15-20°C, pH of 7.5-8.5, ORP of -400 to -350 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0114] Example 4

[0115] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0116] 1) Pre-culture

[0117] A mixed algae solution of Chlorella sp. and Chlamydomonas sp. treated aseptically was inoculated into a semi-open culture system containing 2L of expansion culture medium, the weight ratio of Chlorella sp. to Chlamydomonas sp. was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae solution to the culture medium was 1:10, and light-dark alternation culture was performed under the conditions of temperature 25-35°C, pH 8-9, light intensity 4000 Lux, and light-dark ratio 10:14, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0118] 2) The first stage of domestication

[0119] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0120] (1) A 50 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0121] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 4 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0122] 3) Second stage of domestication

[0123] (1) A 200 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the temperature was maintained for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0124] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 4 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0125] 4) The third stage of domestication

[0126] (1) A 1500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0127] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 4 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0128] Example 5

[0129] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0130] 1) Pre-culture

[0131] A mixed algae solution of Chlorella sp. and Chlamydomonas sp. treated aseptically was inoculated into a semi-open culture system containing 2L of expansion culture medium, the weight ratio of Chlorella sp. to Chlamydomonas sp. was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae solution to the culture medium was 1:10, and light-dark alternation culture was performed under the conditions of temperature 25-35°C, pH 8.5-9, light intensity 4000 Lux, and light-dark ratio 12:12, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 7 days of culture;

[0132] 2) The first stage of domestication

[0133] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0134] (1) A 50 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8.5-9, and a light intensity of 4000 Lux.

[0135] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8.5-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0136] 3) Second stage of domestication

[0137] (1) A 200 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the temperature was maintained for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8.5-9, and a light intensity of 4000 Lux.

[0138] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8.5-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0139] 4) The third stage of domestication

[0140] (1) A 1500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8.5-9, and a light intensity of 4000 Lux.

[0141] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 36 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8.5-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0142] Example 6

[0143] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0144] 1) Pre-culture

[0145] A mixed algae solution of Chlorella sp. and Chlamydomonas sp. treated aseptically was inoculated into a semi-open culture system containing 2L of expansion culture medium, the weight ratio of Chlorella sp. to Chlamydomonas sp. was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae solution to the culture medium was 1:10, and light-dark alternation culture was performed under the conditions of temperature 25-35°C, pH 8-9, light intensity 8000 Lux, and light-dark ratio 12:12, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 7 days of culture;

[0146] 2) The first stage of domestication

[0147] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0148] (1) A 50 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 5 mL / min, and the system was kept stable for 10 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8.5-9, and a light intensity of 8000 Lux.

[0149] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.2 MPa, and cultured for 48 h under the conditions of light intensity of 8000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0150] 3) Second stage of domestication

[0151] (1) A 250 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 5 mL / min, and the system was kept stable for 10 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 8000 Lux.

[0152] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 20 mL / min for 20 min, and ventilation was stopped. The pressure was 0.2 MPa, and cultured for 48 h under the conditions of light intensity of 8000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0153] 4) The third stage of domestication

[0154] (1) A 2000 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 5 mL / min, and the system was kept stable for 10 min. Then, aeration was stopped and the microalgae were cultured for 4 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 8000 Lux.

[0155] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.2 MPa and cultured for 48 h under the conditions of light intensity of 8000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0156] Example 7

[0157] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0158] 1) Pre-culture

[0159] A mixed algae solution of Chlorella sp. and Chlamydomonas sp. treated aseptically was inoculated into a semi-open culture system containing 2L of expansion culture medium, the weight ratio of Chlorella sp. to Chlamydomonas sp. was 1:2, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae solution to the culture medium was 1:10, and light-dark alternation culture was performed under the conditions of temperature 25-35°C, pH 8-9, light intensity 4000 Lux, and light-dark ratio 12:12, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0160] 2) The first stage of domestication

[0161] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0162] (1) A 100 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 20 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0163] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -400ev to -320ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0164] 3) Second stage of domestication

[0165] (1) A 1000 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0166] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 10 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa, and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -400 ev to -320 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0167] 4) The third stage of domestication

[0168] (1) A 2500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 5 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-35°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0169] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 30 mL / min for 20 min, and ventilation was stopped. The pressure was 0.1 MPa and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-35°C, pH of 8-9, ORP of -400 ev to -320 ev, and DO of less than 3 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0170] Example 8

[0171] This example is used to illustrate the method for acclimating microalgae according to the present invention.

[0172] 1) Pre-culture

[0173] A mixed algae liquid of aseptically treated Chlorella sp. and Spirulina sp. was inoculated into a semi-open culture system containing 2 L of expansion culture medium, the weight ratio of Chlorella sp. to Spirulina was 1:1, the total algae concentration was 2.5 g / L, the volume ratio of the microalgae liquid to the culture medium was 1:10, and light-dark alternating culture was performed under the conditions of temperature 25-30°C, pH 8-9, light intensity 2000 Lux, and light-dark ratio 10:14, stirring once every 4 hours, monitoring and recording the microalgae biomass in the culture medium during the culture period, and performing acclimatization culture after 5 days of culture;

[0174] 2) The first stage of domestication

[0175] The pre-cultured mixed microalgae were inoculated into a fully closed culture system containing 2 L of acclimation medium. The concentration of algae in the microalgae solution after inoculation was 4 g / L, and the volume ratio of the microalgae solution to the acclimation medium was 1:10.

[0176] (1) A 100 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 20 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-30°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0177] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 100 mL / min for 20 min, and ventilation was stopped. The pressure was 2 MPa, and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-30°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 2 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0178] 3) Second stage of domestication

[0179] (1) A 500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 20 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-30°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0180] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 150 mL / min for 30 min, and ventilation was stopped. The pressure was 2 MPa, and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-30°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 2 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, the next stage of acclimation was carried out;

[0181] 4) The third stage of domestication

[0182] (1) A 1500 ppm hydrogen sulfide gas was introduced into the microalgae culture system at a rate of 10 mL / min, and the system was kept stable for 20 min. Then, aeration was stopped and the microalgae were cultured for 2 h at a temperature of 25-30°C, a pH of 8-9, and a light intensity of 4000 Lux.

[0183] (2) After repeating step (1) twice, ordinary air was introduced at a rate of 200 mL / min for 30 min, and ventilation was stopped. The pressure was 2 MPa and cultured for 48 h under the conditions of light intensity of 4000 Lux, temperature of 25-30°C, pH of 8-9, ORP of -350 to -300 ev, and DO of less than 2 mg / L. During the culture period, the microalgae were stirred to keep them suspended. When the various monitoring indicators of the mixed microalgae were stable, they were collected to obtain the domesticated microalgae, and their biomass is shown in Table 1.

[0184] Comparative Example 1

[0185] This comparative example is used to illustrate the domestication method of reference microalgae.

[0186] The same as Example 2, except that only pre-culture was performed without acclimation culture. After the culture was completed, the microalgae were collected, and their biomass is shown in Table 1.

[0187] Comparative Example 2

[0188] This comparative example is used to illustrate the domestication method of reference microalgae.

[0189] The same as Example 3, except that only pre-culture was performed without acclimation culture. After the culture was completed, the microalgae were collected, and their biomass is shown in Table 1.

[0190] Test Example 1

[0191] The biomass of the microalgae collected after the cultivation of each example and comparative example was measured, and the results are shown in Table 1.

[0192] Table 1

[0193] serial number Biomass (g / L) Example 1 5.8 Example 2 6.2 Example 3 6.5 Example 4 5.5 Example 5 5.2 Example 6 5.0 Example 7 4.8 Example 8 7.8 Comparative Example 1 9.0 Comparative Example 2 8.8

[0194] It can be seen from the data in Table 1 that the domestication and cultivation of microalgae using the technical solution of the present invention can maintain a relatively high biomass, especially under the culture conditions of Example 8, the biomass of the microalgae can be further increased.

[0195] Test Example 2

[0196] The microalgae obtained by culture in the embodiment and the comparative example were respectively prepared with sodium carbonate to prepare a desulfurization liquid, and the desulfurization liquid was used to treat H 2 The S raw gas is subjected to desulfurization treatment, wherein the concentration of microalgae in the desulfurization liquid is 4 g / L and the concentration of sodium carbonate is 10 g / L.

[0197] In addition, Chlorella and Spirulina were used to domesticate single algae species, and the domesticated microalgae were used to perform H 2 Desulfurization treatment of S, specifically:

[0198] (1) Chlorella control group: The culture method was the same as that in Example 2, except that the algae species was Chlorella sp. in Example 2, the algae species concentration was 2.5 g / L, and the volume ratio of the microalgae solution to the expansion culture medium was 1:10; the pre-cultured microalgae was inoculated into a fully enclosed culture system containing 2 L of acclimation culture medium, the algae species concentration was 4 g / L, and the volume ratio of the microalgae solution to the acclimation culture medium was 1:10; and the microalgae were collected after the acclimation culture (biomass was 4.2 g / L).

[0199] (2) Spirulina control group: The culture method was the same as that in Example 2, except that the algae species was the Spirulina sp. in Example 2, the algae species concentration was 2.5 g / L, and the volume ratio of the microalgae solution to the expansion culture medium was 1:10; after pre-culture, the microalgae were inoculated into a fully enclosed culture system containing 2 L of acclimation culture medium, the total algae species concentration was 4 g / L, and the volume ratio of the microalgae solution to the acclimation culture medium was 1:10; after the culture was completed, the microalgae were collected (biomass was 4.5 g / L).

[0200] Prepare a solution containing H at a concentration of about 1500ppm 2 The desulfurization solutions of the embodiment, comparative example and control group were used to treat H 2 The S raw gas was desulfurized, and each sample was aerated 3 times, 200 mL each time, and maintained for 10 minutes. The content of hydrogen sulfide in the (culture device) was measured after each aeration. The results are shown in Table 2.

[0201] It can be seen from the data of the control group in Table 2 that after a single microalgae is cultured by the domestication method described in the present invention, the desulfurization liquid prepared by the microalgae and sodium carbonate has the effect of removing hydrogen sulfide gas. However, when the content of hydrogen sulfide gas is too high, the efficiency of hydrogen sulfide removal by the microalgae is reduced, the microalgae is poisoned in large quantities, and the sulfur resistance is poor.

[0202] Table 2

[0203]

[0204]

[0205] It can be seen from the data in Table 2 that the use of the technical solution of the present invention for acclimatization and cultivation of microalgae can significantly improve the sulfur tolerance and desulfurization efficiency of the microalgae.

[0206] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for domesticating microalgae, characterized in that: The method comprises: inoculating microalgae onto a domestication culture medium, introducing sulfur-containing gas and sequentially performing at least two stages of domestication culture to obtain domesticated microalgae; Among them, in at least two stages of domestication and cultivation, the steps of domestication in each stage include: S1: After introducing sulfur-containing gas into the acclimation medium and maintaining it for 2-15 min, ventilation is stopped and the acclimation culture is carried out for 1-6 h; S2: Repeat step S1 at least once; S3: Then, oxygen-containing gas is introduced into the acclimation medium and maintained for 10-30 min, and then aeration is stopped and cultured for 20-72 h; Wherein, the concentration of the sulfur-containing gas introduced in each stage of acclimatization is greater than the concentration of the sulfur-containing gas introduced in the previous stage.

2. The method according to claim 1, wherein: The microalgae are mixed microalgae; Preferably, the microalgae strains in the mixed microalgae belong to at least one of green algae, blue algae, diatoms and red algae. More preferably, the mixed microalgae are a combination of at least two green algae, a combination of green algae and blue algae, or a combination of blue algae and diatoms. Preferably, the green algae is selected from at least one of Chlorella, Chlamydomonas and Scenedesmus; Preferably, the cyanobacteria is selected from at least one of Cyanobacterium sphaeroides, Oscillatoria sphaeroides, Nostoc sphaeroides and Spirulina; Preferably, the diatom is selected from at least one of Melostomia, Chaetoceros and Cyclotella; Preferably, the red algae is selected from red hair algae and / or polysiphonia; Preferably, the volume ratio of the microalgae to the acclimation medium is 1:50-1:4; Preferably, the weight ratio between any two algae in the mixed microalgae is 0.1-100, preferably 0.5-20.

3. The method according to claim 1 or 2, wherein: The sulfur-containing gas includes hydrogen sulfide and / or sulfur dioxide; Preferably, the concentration of sulfur-containing gas is below 3000 ppm; Preferably, the amount of hydrogen sulfide and / or sulfur dioxide introduced per liter of acclimation medium is 3-375 mL, preferably 25-100 mL; Preferably, the amount of oxygen in the oxygen-containing gas introduced into the acclimation medium is 10-1000 mL, preferably 20-650 mL.

4. The method according to any one of claims 1 to 3, wherein: In at least two stages of acclimation and cultivation, the concentration of the sulfur-containing gas introduced in each acclimation stage is: the concentration of the sulfur-containing gas introduced in the first stage is 10-120 ppm; Preferably, the concentration of the sulfur-containing gas introduced in the second stage is 80-1200 ppm.

5. The method according to any one of claims 1 to 4, wherein: The at least two-stage acclimation culture includes at least three-stage acclimation culture; Preferably, the concentration of the sulfur-containing gas introduced in the first stage is 10-120 ppm; Preferably, the concentration of the sulfur-containing gas introduced in the second stage is 80-1200 ppm; Preferably, the concentration of the sulfur-containing gas introduced in the third stage is 800-3000 ppm.

6. The method according to any one of claims 1 to 5, wherein: In step S1, the conditions for acclimatization and culture include: light intensity of 100-25000 Lux, preferably 2000-10000 Lux; Preferably, the culture temperature is 10-45°C, more preferably 12-30°C; Preferably, the culture pH is 6-9.5, more preferably 7-9.

7. The method according to any one of claims 1 to 6, wherein: In step S3, the culture conditions include: light intensity of 100-25000 Lux, preferably 2000-10000 Lux; Preferably, the light-to-dark ratio is 6:18-24:0, more preferably 8:16-14:10; Preferably, the pressure is 0.1-3 MPa, more preferably 0.15-2 MPa; Preferably, the culture temperature is 10-45°C, more preferably 12-30°C; Preferably, the culture pH is 6-9.5, more preferably 7-9; Preferably, the redox potential is -450 to -150 eV, more preferably -450 to -300 eV; Preferably, the dissolved oxygen content is 10 mg / L or less, more preferably 4 mg / L or less.

8. The method according to any one of claims 1 to 7, wherein: The method further comprises: before inoculating the microalgae into the acclimation medium, inoculating an algae solution containing the microalgae into the expansion culture medium for pre-culture; Preferably, the pre-culture conditions include: culture time of 3-15 days, preferably 4-8 days; light intensity of 100-25000 Lux, preferably 2000-10000 Lux; light-dark ratio of 6:18-24:0, preferably 8:16-14:10; culture temperature of 10-45° C., preferably 12-30° C.; culture pH of 6-9.5, preferably 7-9; Preferably, the volume ratio of the microalgae liquid to the expansion culture medium is 1:50-1:

4.

9. The method according to any one of claims 1 to 8, wherein: The acclimation culture medium comprises: 100-700 mg / L NaNO3, 20-180 mg / L KH2PO4, 600-2500 mg / L NaHCO3, and 1000-5000 mg / L Na2CO3.

10. The method according to claim 9, wherein: The acclimation culture medium also includes: 30-180 mg / L vitamin B1, 15-80 mg / L vitamin B12, 15-80 mg / L vitamin H, 1000-5000 mg / L disodium EDTA, 3-30 mg / L CuSO4, 10-60 mg / L ZnSO4, 50-250 mg / L MnCl2, 50-200 mg / L CaCl2, and 20-120 mg / L CoCl2.

11. The method according to claim 8, wherein: The expansion culture medium comprises: 200-1000 mg / L NaNO3, 20-100 mg / L NaH2PO4, 40-200 mg / L KH2PO4, and 70-350 mg / L Na2CO3.

12. The method according to claim 11, wherein: The expansion culture medium also includes: 30-180 mg / L vitamin B1, 15-80 mg / L vitamin B12, 1000-5000 mg / L disodium EDTA, 8-60 mg / L CuSO4, 15-85 mg / L ZnSO4, 25-150 mg / L MgSO4, 70-350 mg / L MnCl2, 60-350 mg / L CaCl2, 120-500 mg / L FeCl3, and 20-100 mg / L CoCl2.

13. Use of the domesticated microalgae obtained by the method according to any one of claims 1 to 12 in treating sulfur-containing gases.

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